Regarding my friend’s question about CS 2002 discount interaction:
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Order Subtotal Discount
The Order Subtotal Discount applies discounts to the order subtotal. An order subtotal discount is an order-level discount that applies to all products in a shopping basket. For example, free shipping is a type of order-level discount: you can give users free shipping for all products in their basket. Order-level discounts delivered with Commerce Server are free shipping, and a percentage or dollar amount off the total price. You cannot apply multiple discounts to an order-level discount. Order-level discounts have an implicit limit of 1.
To handle refunds properly, order-level discounts should be distributed across all line items. Commerce Server 2002 distributes percentage off discounts and dollar off discounts. For information about distributing order-level discounts see Distributing Order-level Discounts.
Note
If you want to restrict a particular item from participating in an order-level discount (for example, an item in high demand), see the “OrderLevelDiscountApply” component at :Program FilesMicrosoft Commerce Server 2002SDKSamplesOrder ProcessingOrderLevelDiscountComponents. This component allows you to specify the name of a key that specifies whether the item can receive an offer.
This feature does not apply to item-level discounts, but can be added with custom configuration work.
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Multiple Discounts
Discount interaction policies are rules that determine whether an item can receive multiple discounts or multiple awards. Commerce Server 2002 supports four different discount interaction policies.
- A condition item can be reused as another condition item. Instructs Commerce Server 2002 that a condition item used to qualify for an offer can be reused again to qualify for another offer.
- A condition item can be reused as an award item. Instructs Commerce Server 2002 that an item used to qualify for a discount can still be eligible to receive an offer.
- An award item can be reused as a condition item. Instructs Commerce Server 2002 that an item upon which an award was given can still be used to qualify for other offers.
- An award item can be used as another award item. Instructs Commerce Server 2002 that an item upon which an award was given is eligible to receive additional offers, for example, an item can receive multiple awards.
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Other links related to discounts
http://msdn.microsoft.com/en-us/library/ee785199(CS.20).aspx
Processing Discounts